Synthesis Of PP-g-PA6 Graft Copolymer And Compatibility Of PP/PP-g-PA6/PA6 Blends

Through the mixing of different polymers to prepare a new kind of blending materials, these methods have attracted much attention because it can not only fully utilize existing resources of a wide variety of polymer materials, but also obtain excellent properties of new materials. The ultimate performance of obtained blend depends not only on components itself, but also the compatibility between components. Improving the compatibility of incompatible systems is the key problem of improving material properties. In this paper, by the introduction of the incompatible system with polypropylene grafted polyamide 6 (PP-g-PA6) as the compatibilizer of the blends, the effects of the compatibility characteristics and impact resistance(-20℃) of blends were characterized. In the same time, the hydrophilicity of PP-g-TMI PP-g-PA6 and PP/PP-g-PA6/PA6 blends were investigated to study the effects of polar groups, polar grafted chains and polar component on the hydrophilicity of polypropylene.TMI is chosen as a functionalizing monomer with-NCO functional group and attached to the main chain of PP by melt free radical grafting to prepare macroactivator. The graft copolymer PP-g-PA6 is formed through the activated anionic situ polymerization of CL in the presence of sodium caprolactam (NaCL) as a catalyst and PP-g-TMI as a activator, By PP-g-PA6 reaction torque change, DSC and FTIR, PA6 grafted copolymerization reaction is confirmed.The results of SEM of PP/PP-g-PA6/PA6 blends show that in PP and PA6 blends adding 2wt% compatibilizer PP-g-PA6, the biggest dispersed particle size of PA6 dispersed phase decreases from more than 10μm down to 2μm and impact resistance(-20℃) increases from 0.85 KJ/m2 raised to 2 KJ/m2. Increasing the dose to 5wt% of PP-g-PA6, the biggest dispersed particle size of PA6 dispersed phase is reduced to around 1μm and the reducing trend is not significant. The results of impact resistance(-20℃) show that adding more than 2wt% of compatibilizer has little good effction on further improving the impact resistance of blendsStuding the polar groups, polar grafted chains and polar components on the hydrophilicity of PP shows that with the increase of grafting yield of TMI, water contact angles of PP-g-TMI decrease to 91.4°(pure PP is 100.3°), hydrophilicity of PP is improved.With the increase of PA6 graft chain length, water contact angles of PP-g-PA6 decrease to 76.9°, hydrophilicity of PP is improved significantly;After PP-g-PA6 is added to blends as compatibilizer, water contact angles of PP/PP-g-PA6/PA6 blends can be reduced to 75.3°, hydrophilicity of blends improved significantly.